A HISTORY OF DORSET 



by the present working of the quarries, yet, if they 

 were taken from you, I believe you might find the 

 want of them in very little time ; and you may be 

 sure that care will be taken both to maintain the 

 Queen's right, and that such only be employed in the 

 quarries as will work regularly and quietly, and submit 

 to proper and reasonable directions, which I leave you 

 to consider of, and am 



Your friend, 



Chr. Wren. 



P.S. — I am sorry Mr. Wood has paid you the 

 tunnage money, but if I have not a better account of 

 your behaviour, I shall ende.tvour that you be made 

 to refund it ; and whether your jury present Mr. 

 Wood or not for the stone, 'tis all one to me. If you 

 take upon you to pay the duty for any stone, for St. 

 Paul's or other uses that I give orders for, you shall 

 not have one farthing allowed you for it. 



To Mr. John Elliott, Bart. Comber, Thomas 

 Ouseley, Ben Stone, Henry Atwel, Robert Gibbs, at 

 Portland."' 



The allusion to Greenwich in the above letter 

 is explained by reference to the Treasury Papers of 

 1702, concerned with the report of James Moun- 

 tague to the Lord High Treasurer, on the petition 

 of the directors of Greenwich Hospital touching 

 the demand by the islanders of Portland of lid. 

 per ton and bd. by the commissioners of all stone 

 shipped for the use of the hospital. In this 

 report we find it set forth that the whole island 

 is the queen's manor. Also that time out of 

 mind a duty had been paid of is. z ton, 3^/. of 

 which was in consideration of the damage done 

 to the herbage by the quarry workings.*^'' 



We are unable here to trace further in any 

 detail the history of the Portland quarries, but a 

 few notes may be allowed on the different strata 

 of stone and the fashion of working. In a typical 

 quarry the strata in descending order may be 

 found *' as follows : — 



ft. in. 



Mould 10 



Shivered stone and rubble — the 

 debris of Purbeck stone and slate 



stone 10 o 



Bacon tier with layers of sand ,.19 



Aish stone ^ 3 



Soft Burr 16 



Great Dirt-bed (with trees and Cy- 



cadeae) 10 



Cap Rising 20 



These are excavated and then the top-cap is 

 reached, with a thickness of from 8 to I O ft. A 



"= Hutchins, Hist. Dorset, ii, 818. 



"■^ Cal. Treas. Papers, 1702, vii, 498. 



"* It must be remembered, however, that the thick- 

 ness of the different strata varies considerably according 

 to the nature and position of the quarry. A shorter 

 section of a quarry as known among the quarrymen is 

 furnished us by Mr. J. Merrick Head. The names 

 are in descending order : — Soil, Rubble, Soft Burr, 

 Dirt Bed, Cap, Skull-Cap, Roach, Whitbed, some- 

 times Curf Bed, Base Bed, Flint Bed. 



very thin dirt-bed follows between this and tiie 

 Skull-Cap (2 ft. 6 in.), which is succeeded by the 

 True Roach, which averages from 2 ft. 6 in. to 

 3 ft. The Top-Cap, Skull-Cap, and True Roach 

 are generally blasted off to get at the ' merchant- 

 able' stone beneath. For heavy engineering 

 works, however, True Roach, which is very 

 light brown in colour, furnishes excellent mate- 

 rial. It weathers well, is tough and strong, and 

 owing to its resistance to the action of water is 

 suitable for dock and sea-walls and break- 

 waters.*' 



Next below the True Roach are found the 



Whitbed 8 to 10 ft. 



Curf or Bastard Roach with 



flints 



Basebed Roach 



Basebed stone 5 to 6 ft. 



Flat beds or flinty tiers 



Whitbed *' is in many respects the most valu- 

 able of the Portland series. The material with 

 which the fine oolitic grains are cemented to- 

 gether is hard and crystalline. This stone, if of 

 good quality, weathers excellently, and is markedly 

 superior in this respect to Basebed, which re- 

 sembles it in appearance, but is softer, more 

 easily worked, and adapted rather for internal 

 work. Bastard Roach or Curf may be distin- 

 guished from True Roach by the absence of the 

 fossil known as the Portland Screw {Cerlthium 

 Portlandicum), which seldom if ever occurs in 

 Curf. Its weathering qualities are poor. 



Smeaton,^' the builder of the Eddystone Light- 

 house, on his visit to the Portland quarries, 

 remarked how — 



When tlie merchantable blocks are cleared of the cap 

 the quarrymen proceed to cross-cut the large flats 

 which are laid bare with wedges. The beds being 

 thus cut into distinct lumps the quarryman, with a 

 tool called a ' kevel,' which is at one end a hammer 

 and at the other an axe, whose edge is so short or 

 narrow that it approaches towards the shape of a pick, 

 by a repetition of sturdy blows soon reduces a piece of 

 stone, by his eye, to the largest square figure which it 

 will admit. 



At the present day blocks of from 10 to 12 tons 

 can be obtained easily if required. The mode 

 of carriage of stone for shipment down the hill 

 was formerly by large wooden trollies with solid 

 wheels of wood, drawn by a team of horses, three 

 behind, two abreast, and one following — the 

 three behind operating as a drag. 



The whole island is full of the quarries, which 

 are wrought from open faces. The stone is 



*' It has also been used for fortifications, as it was 

 found by experiments to offer more resistance to shell- 

 fire than even Cornish granite. 



*' The colour is more commonly white, but a 

 brownish hue is perceptible in some of the best stone. 

 Notes on Building Construction, iii, ' Portland Stone.' 



'^ Eddystone Lighthouse (1791), 62 et seq. 



342 



